• Pressure Seal Backseat increasespacking life and provides maximum valveintegrity by ensuring a positive internalstop for the valve stem and disc assembly,securely isolating packing from linepressure when valve is fully open.• Cartridge Type Packing Chamber withsecure, leak-proof bonnet allows rapidaccess to valve trim for inspection andmaintenance. Pressure boundary is sealedat the smallest diameter possible to ensuremaximum strength and low stress.• Thermal Isolation of the packing chamberincreases packing life. The Stainless Steelpacking chamber is a separate unit fromthe body and therefore, eliminates theneed to remove or change packing afterstress relieving.